1,2,4-thiadiazolyl-ureas

ABSTRACT

N-(3-(ALKYL, ALKYLMERCAPTO, DIALKYLAMINO AND PHENYLSUBSTITUTED)-1,2,4-THIADIAZOL-5-YL) - N - (UNSUBSTITUTED AND ALKYL-SUBSTITUTED)-N&#39;&#39;,N&#39;&#39;-(MONO- AND DI-ALKYL-SUBSTITUTED) UREAS WHICH POSSESS HERBICIDAL PROPERTIES, AND WHICH MAY BE PRODUCED BY CONVENTIONAL METHODS.

United States Patent Office Ser. No. 862,908 Claims priority,application ('g'ermauy, Sept. 19, 1967, Int. or. 067.1 91/60 US. Cl.260-3068 D 13 Claims ABSTRACT OF THE DISCLOSURE N-[3-(alkyl,alkylmercapto, dialkylamino andphenylsubstituted)-1,2,4-thiadiazol-5-yl] N [unsubstituted andalkyl-substituted]-N',N'-[monoand di-alkyl-substituted] ureas whichpossess herbicidal properties, and which may be produced by conventionalmethods.

This is a continuation-in-part application of copending US. application,Ser. No. 756,296, filed Aug. 29, 1968, now abandoned.

The present invention relates to and has for its objects the provisionfor particular new 1,2,4-thiadiazolyl ureas, i.e. N-[3-(alky1,alkylmercapto, dialkylamino and phenylsubstituted) 1,2,4thiadiazol-5-yl]-N-[unsubstituted and alkyl-substituted]-N',N'-[monoanddi-alkylsubstituted] ureas, which possess valuable, especiallyselective, herbicidal properties, active compositions in the form ofmixtures of such compounds with solid and liquid dispersible carriervehicles, and methods for producing such compounds and for using suchcompounds in a new way, especially for combating weeds, undesiredplants, and the like, with other and further objects becoming apparentfrom a study of the within specification and accompanying examples.

It is known that thiazolyl ureas, such as N-(4 methyl-1,3-thiazol-2-yl)-N-methyl urea (A), can be used as herbicides (seeBelgian Pat. 679,138).

It has now been found, in accordance with the present invention, thatthe particular new 1,2,4-thiadiazolyl ureas having the general formula.

in which R is selected from the group consisting of alkyl having :1-4carbon atoms, alkylmercapto having 1-4 carbon atoms, di-alkyl-aminohaving 1-4 carbon atoms in each alkyl moiety and phenyl,

-R is selected from the group consisting of hydrogen and alkyl having1-4 carbon atoms,

R" is selected from the group consisting of hydrogen and alkyl having1-4 carbon atoms, and

R' is alkyl having 1-4 carbon atoms,

exhibit strong herbicidal, in particular selective herbicidalproperties.

Analogous carboxylic acid (1,2,4-thiadiazol-5-yl)-amides havingparticularly effective, especially selective, herbicidal activity aredisclosed and claimed in copending US. application Ser. No. 756,310,filed Aug. 29, 1968,

3,686,198 Patented Aug. 22, 1972 now US. Pat. 3,629,275, whereasanalogous N-substituted S-amino-1,3,4-thiadiazoles having particularlyeffective, especially selective, herbicidal activity, are disclosed andclaimed in copending US. application Ser. No. 756,284, also filed Aug.29, 1968.

The present invention also provides a process for the production of a1,2,4-thiadiazolyl urea of Formula I above in which [a] aS-aminothiadiazole of the formula:

F i i" l& C-NH S (113} in which R and R are the same as defined above isreacted, in the presence of a solvent, with an isocyanate of theformula:

R'--N=C=0 (11b) in which R'" is the same as defined above, or

[b] a S-aminothiaidazole of Formula Ila is reacted, in the presence of asolvent and an acid binder, with an acid chloride of the formula:

N-COOl R'" (He in which R" and -R" are the same as defined above, or [c]a urethane of the formula:

R?N R bi (J-IlF-COOR in which R and R are the same as defined above, andR is a methyl or phenyl radical is reacted with an amine of the formula:

R (He) in which R" and R'" are the same as defined above.

It is very surprising that the 1,2,4-thiadiazolyl ureas according to thepresent invention have a stronger herbicidal activity and a betterselective herbicidal activity than the previously known thiazolyl ureas.

If methyl isocyanate and 3-phenyl-5-amino-1,2,4- thiadiazole are used asreactants, the reaction according to [a] can be represented by thefollowing formula scheme:

(IIaa) (IIbb) CaHs1l N If 3-phenyl-5-amino-1,2,4-thiadiazole anddimethylcarbamic acid chloride are used as starting materials, the

reaction according to [b] can be represented by the following formulascheme;

(line) (1100) Cant-T /CHa S NH-COOCII HN\ (IIee) nan Advantageously, inaccordance with the present invention, in the various formulae herein:

R represents Alkyl having 1-4 carbon atoms, such as methyl, ethyl, nandiso-propyl, n-, iso-, sec.- and tert.-butyl, and the like, especiallymethyl, ethyl, nand iso-propyl, and particularly C 4; alkyl; or

Alkylmercapto having 14 carbon atoms, such as methyl to tert.-butylinclusive, as defined above, and the like, -mercapto, especially Calkylmercapto, and preferably methyl-mercapto; or

Di-alkylarnino having 14 carbon atoms in each alkyl moiety, such asdimethyl to tert.-butyl inclusive, as defined above, and the like,-amino, including mixed methylwith -ethyl, -n-propyl, -isopropyl,-n-butyl, -isobutyl, -sec.- butyl, -tert.-butyl; ethylwith -n-propyl,-isopropyl, -nbutyl, -isobutyl, -sec.-butyl, -tert.-butyl; n-propylwith-isopropyl, -n-butyl, -isobutyl, -sec.-butyl, -tert.-butyl;isopropylwith -n-butyl, -isobutyl, -sec.-butyl, tert.-butyl; n-butylwith-isobutyl, -sec.-butyl, -tert.-butyl; isobutylwith -sec.-butyl,-tert.-butyl; sec.-butylwith tert.-butyl, etc., and the like, -amino,especially di-C alkyl-amino, more especially where both alkyl moietiesare the same, and particularly dimethylamino; or phenyl;

R represents hydrogen; or alkyl having 1-4 carbon atoms, such as methylto tert.-butyl inclusive, as defined above, and the like, specially Calkyl, and particularly methyl;

R" represents hydrogen; or alkyl having l-4 carbon atoms, such as methylto tert.-butyl inclusive, as defined above, and the like, especially Calkyl, and particularly methyl; and

R' represents alkyl having 1-4 carbon atoms, such as methyl totert.-butyl inclusive, as defined above, and the like, especially Calkyl, and particularly methyl.

In accordance with a particular feature of the present invention, Rrepresents C especially C alkyl, or phenyl; R represents hydrogen or Cespecially C alkyl, or phenyl; R represents hydrogen or C especially Calkyl; R" represents hydrogen or C especially C alkyl, and preferablyhydrogen and C alkyl; and R represents C especially C alkyl.

The starting materials of Formulae 11a, 11b, 11c and He above arealready known.

The starting materials of Formula IId above have not hitherto been knownbut they can be prepared by the usual methods for the preparation ofurethanes from the thiadiazolyl amines of Formula Ila, for example byreaction with chloroformic acid esters in the presence of enert organicsolvents, such as benzene, and acid binders, such as trimethyl amine andpyridine, at temperatures between about 0 C. and 40 C.

The term solvent as used herein includes mere diluents. All inertorganic solvents are suitable for the process variants [a], [b] and [c].Preferred solvents include hydrocarbons, such as benzene and toluene;ethers, such as diethyl ether, tetrahydrofuran and dioxan; ketones, suchas acetone; esters, such as ethyl acetate; and polar solvents, such asdimethyl formamide and acetonitrile.

As acid binders, all customary acid-binding agents can be used.Preferred acid binding agents include alkali metal hydroxides, such assodium hydroxide and potassium hydroxide, as well as alkali metalcarbonates, such as potassium carbonate. Particularly suitable aretertiary amines, such as pyridine and triethyl amine.

The reaction temperatures can be varied within a fairly wide range. Ingeneral, the reaction is carried out at substantially between about0-120" C., and preferably between about 10120 C.

When carrying out the process of the invention, equimolar amounts ofstarting materials are expediently used. In process variants [a] and[b], the most favourable temperature is about 1080 C.; in processvariant [c] it is about -120 C. Moreover, here the reaction is carriedout expediently under pressure. As solvent in this case a fairly largeexcess of amine can also be used. The working up of the reaction mixturemay be carried out in the usual manner.

Advantageously, the active compounds according to the present inventioninfluence plant growth and can therefore be used as defoliating agentsand weedkillers to facilitate harvest. The instant compounds are,however, quite particularly suitable for the control weeds. By weeds aremeant in the widest sense all plants which grow in places where they arenot desired. Whether the active compounds according to the presentinvention act as total or selective herbicides depends essentially onthe amount applied as the artisan will appreciate.

The active compounds according to the present invention can be used, forexample, in the case of the following plants: dicotyledons, such asmustard (Sinapis), cress (Lepidium), cleaver (Galium), common chickweed(Stellaria), mayweed (Matricaria), smallfiower Galinsoga (Galinsoga),fathen (Chenopodium), stinging nettles (Urtica), groundsel (Senecio),cotton (Gossypium), beets (Beta), carrots (Daucus), beans (Phaseolus),potatoes (Solanum), coffee (Cofea); monocotyledons, such as timothy(Phleum), bluegrass (Poa), fescue (Fustuca), goosegrass (Eleusine),foxtail (Setaria), ryegrass (Lolium), cheat (Bromus), barnyard grass(Echinochloa), maize (Zea), rice (Oryza), oats (Avena), barley(Hordeum), wheat (Triticum), millet (Panicum), sugar cane (Saccharum);and the like.

The active compounds according to the instant inven tion can beutilized, if desired, in the form of the usual formulations orcompositions With conventional inert (i.e. plant compatible orherbicidally inert) pesticidal diluents or extenders, i.e., diluents orextenders of the type usable in conventional pesticidal formulations orcompositions, e.g. conventional pesticidal dispersible carrier vehicles,such as solutions, emulsions, suspensions, emulsifiable concentrates,spray powders, pastes, soluble powders, dusting agents, granules, etc.These are prepared in known manner, for instance by extending the activecompounds with dispersible liquid diluent carriers and/or dispersiblesolid carriers optionally with the use of carrier vehicle assistants,e.g., surface-active agents, including emulsifying agents and/ordispersing agents, whereby, for example, in the case where water is usedas diluent, organic solvents may be added as auxiliary solvents. Thefollowing may be chiefly considered for use as carrier vehicles for thispurpose: dispersible liquid diluent carriers including inert organicsolvents such as aromatic hydrocarbons (e.g. benzene, toluene, xylene,etc.), halogenated, especially chlorinated, aromatic hydrocarbons (e.g.chlorobenzenes), parafiins (e.g. petroleum fractions), chlorinatedaliphatic hydrocarbons (e.g. methylene chloride, etc.), alcohols (e.g.methanol, ethanol, propanol, butanol, etc.), ethers, ether-alcohols(e.g. glycol monomethyl ether, etc), amines (e.g. ethanolamine, etc.),amides (e.g. dimethyl formamide, etc.), sulfoxides (e.g. dimethylsulfoxide, etc.) ketones (e.g. acetone, etc.), and/or water; as well asdispersible finely divided solid carriers, such as ground naturalminerals (e.g. kaolins, alumina, silica, chalk, i.e., calcium carbonate,talc, kieselguhr, etc.), and ground synthetic minerals (e.g. highlydispersed silicic acid, silicates, e.g., alkali silicates, etc.);whereas the following may be chiefiy considered for use as carriervehicle assistants, e,g., surface-active agents, for this purpose:emulsifying agents, such as nonionic and/ or anionic emulsifying agents(e.g. polyethylene oxide esters of fatty acids, polyethylene oxideethers of fatty alcohols, alkyl sulfonates, aryl sulfonates, etc., andespecially alkyl arylpolyglycol ethers, magnesium stearate, sodiumoleate, etc.); and/or dispersing agents, such as lignin, sulfite wasteliquors, methyl cellulose, etc.

As will be appreciated by the artisan, the active compounds according tothe instant invention may be employed alone or in the form of mixtureswith one another and/or with such solid and/or liquid dispersible carrer vehicles and/or with other known compatible active agents, especiallyplant protection agents, such as other herbicides, fungicides,insecticides, bactericides, etc., 1f desired, or in the form ofparticular dosage preparations for specific application made therefrom,such as solutions, emulsions, suspensions, powders, pastes, and granuleswhich are thus ready for use.

As concerns commercially marketed preparations, these generallycontemplate carrier composition mixtures in which the active compound ispresent in an amount substantially between about 0.1-95% by weight, andpreferably 05-90% by weight, of the mixture, whereas carrier compositionmixtures suitable for direct applicat on or field application generallycontemplate those in which the active compound is present in an amountsubstantially between about 0.01l%, preferably 0.02%, by weight of themixture. Thus, the present invention contemplates over-all compositionswhich comprise mixtures of a d spersible carrier vehicle such as (l) adispersible carrier solid and/or (2) a dispersible carrier liquid suchas an inert organic solvent and/or water preferably including a surfaceactive effective amount of a conventional pesticide carrier vehicleassistant, e.g., a surface-active agent, such as an emulsifying agentand/or a dispersing agent, and an amount of the active compound which iseffective for the purpose in question and which is generally betweenabout 0.01-95 by weight of the mixture.

While the active compounds can be used according to the pre-emergencemethod, they are also effective when used according to thepost-emergence method, i.e. both before and after the emergence of theplants.

In general, the amounts of the active compound actually applied are'substantially between about 0.2550 or 0.340 or 03-20 or 0.3- or 1-20kg./hectare, and preferably between about 0.3-10 or 2-10 kg./hectare,apart from any carrier vehicle which may also be present.

The active compounds can also be used in accordance with the well knownultra-low-volume process with good success, i.e. by applying suchcompound if normally a liquid, or by applying a liquid compositioncontaining the same, via wery effective atomizing equipment in extremelyfinely divided form, i.e. mist form, for example by airplane cropspraying techniques. Only a few liters/ hectare are needed, and oftenamounts up to about 1 quart/acre, preferably 2-16 fluid ounces/acre, aresufiicient. In this process it is possible to use highly concentratedliquid compositions with said liquid carrier vehicles containing fromabout 40 to about by weight of active compound or even the activesubstance alone, e.g. about 40-100% by weight of the active compound.

Furthermore, the present invention contemplates methods of selectivelycontrolling or combating undesired plants, e.g., weeds and the like,and/or of defoliating plants, which comprise applying to at least one of(a) such weeds, plants, etc. and (b) their habitat, i.e., the locus tobe protected, a herbicidally effective, or defoliating, amount of theparticular active compound of the invention alone or together with acarrier vehicle as noted above. The instant formulations or compositionsare applied in the usual manner, for example, by spraying, atomizing,scattering, dusting, watering, sprinkling, and the like, whether forpre-emergence application to the soil or postemergence application tothe weeds.

It will be realized, of course, that in connection with thepre-emergence use of the instant compounds as Well as the post-emergenceuse thereof, the concentration of the particular active compoundutilized in admixture with the carrier vehicle will depend upon theintended application and may be varied within a fairly -wide rangedepending upon the weather conditions, the purpose for which the activecompound is used, e.g. selective or total herbicide, and the plantswhich are to be controlled or protected. Therefore, in special cases, itis possible to go above or below the aforementioned concentration rangesand amounts/hectare.

The following examples illustrate, without limitation, the henbicidalactivity of the particular active compounds of the present invention.

EXAMPLE 1 Pre-emergence test Solvent: 5 parts by weight acetoneEmulsifier: 1 part by weight alkylaryl polyglycol ether To produce asuitable preparation of the particular active compound, 1 part by weightof such active com pound is mixed with the stated amount of solvent, thestated amount of emulsifier is then added and the resulting concentrateis diluted with water to the desired final concentration.

Seeds of the test plants are sown in normal soil and, after 24 hours,watered with the preparation of the given active compound. It isexpedient to keep constant the amount of water per unit area. The activecompound concentration in the preparation is of no importance, only theamount of active compound applied per unit area being decisive. Afterthree weeks, the degree of damage to the test plants is determined andcharacterized by the values 0-5, which have the following meaning:

0-no effect lslight damage or delay in growth 2marked damage orinhibition of growth 3heavy damage and only deficient development oronly 50% emerged 4plants partially destroyed after germination or only25% emerged 5-plants completely dead or not emerged.

The particular active compounds tested, the amounts applied and theresults obtained can be seen from the following Table l.

TABLE 1.PRE-EMERGENCE TEST Active compound applied in kg] Echino- Chem)-51- Got- Activc compound hectare chloa podium napls Oats ton Wheat (A)CHS 40 4-5 5 4 4 4-5 I! I 4 5 5 4 4 4 GHQ-C C-NH-C-NIL-CH; 10 4 5 4 3-43 4 4 ll 5 3 4 2-3 3 1 a 2. 5 2 2-3 1 2 n 1 (known) (3 CHz-CH N I CH; 405 5 5 5 5 5 CH3 N 10 5 5 5 5 5 5 -N 5 5 5 5 5 2 4 S 2. 5 5 5 4 4-5 1 2 OO-NH-CH; 1. 4 5 5 4 0 1 (4,) CH3- N /CHa 48 5 5 5 5 5 4-5 1 5 5 5 5 4 3-N 5 5 5 5 5 3 2 S 2. 5 4 5 5 5 2 0 C O-NH-CH;

(51)- 0211 N 5 5 5 5 4 5 10 5 5 5 4-5 2 3 5 5 4 5 4 0 2 \S NHC O-NH-CH32. 5 4 3 6 3 0 1 (6 CH5 40 5 5 5 5 5 4 10 5 5 5 5 3-4 2 OH N 5 5 5 5 4-52 0 2. 5 4-5 5 5 3 0 0 CH3 N -NHC ONHCHa 7 n-CaH1- N 40 5 5 5 5 5 4 I)10 5 5 5 5 3-4 2 N 5 5 5 5 4-5 2 0 s NH-C O-NH-CH: 2. 5 4-5 5 5 3 0 0(16 i-C3H7 N 1. 25 5 5 5 4 2 2 C2H 0. 625 4 5 5 3 0 0 N 0. 3125 3 5 5 30 0 N-C ON H-C Hz 17 n-C H N 5 5 5 5 2-3 3-4 4 1) a 1 02115 2. 5 5 5 52-3 2 3 N 14 25 5 5 5 0 0 2 s N-C ONIICH3 0. 625 5 5 3 0 0 0 (18 i-CgH;N 5 5 5 5 4-5 2 4-5 2. 5 5 5 5 4-5 1 4 H 1. 25 5 5 5 4 0 3-4 EXAMPLE 2Post-emergence test Solvent: 5 parts by weight acetone Emulsifier: 1part by weight alkylaryl polyglycol ether til just dew moist. Afterthree weeks, the degree of damage to the plants is determined andcharacterized by the values 0-5, which have the following meaning:

0no effect l-a few slightly burnt spots 2marked damage to leaves 3someleaves and parts of stalks partially dead 4-plant partially destroyed5-plant completely dead.

The particular active compounds tested, their concentrations and theresults obtained can be seen from the following Table 2.

TABLE 2.-POST-EMERGENGE TEST Active Compound Concentrati on of activecompound in percent Echino- Chenechloa podium napis Urtica Oats Cot-

ton

Wheat (Db-mm warm-blooded creatures and higher plants for more effectivecontrol and/or elimination of weeds by selective application of suchcompounds to such weeds and/or their habitat. Nevertheless, the instantcompounds possess total herbicidal action when used in large quantities,although selective herbicidal action is obtained when used in smallerquantities. As contemplated herein, the term weeds is meant to includenot only weeds in the narrow sense, but also in the broad sense, wherebyto cover all plants and vegetation considered undesirable for theparticular purposes in question.

It will be appreciated that the instant specification and examples areset forth by way of illustration and not limitation, and that variousmodifications and changes may be made without departing from the spiritand scope of the present invention which is to be limited only by thescope of the appended claims.

What is claimed is:

1. 1,2,4-thiadiazolyl urea of the formula in which R is selected fromthe group consisting of alkyl having 1-3 carbon atoms, alkylmercaptohaving 1-4 carbon atoms, di-alkyl-amino having 1-4 carbon atoms in eachalkyl moiety, and phenyl, R' is selected from the group consisting ofhydrogen and alkyl having 1-4 carbon atoms, R" is selected from thegroup consisting of hydrogen and alkyl having 1-4 carbon atoms, and R isalkyl having 1-4 carbon atoms.

2. Compound according to claim 1 wherein R is selected from the groupconsisting of alkyl having 1-3 carbon atoms, alkylmercapto having 1-2carbon atoms, di-alkylamino having 1-2 carbon atoms in each alkylmoiety, and phenyl, R is selected from the group consisting of hydrogenand alkyl having 1-2 carbon atoms, R" is selected from the groupconsisting of hydrogen and alkyl having 1-2 carbon atoms, and R is alkylhaving 1-3 carbon atoms.

3. Compound according to claim 1 wherein R is selected from the groupconsisting of C alkyl and phenyl, R is selected from the groupconsisting of hydrogen and C alkyl, R" is selected from the groupconsisting of hydrogen and C alkyl, and R' is (1 alkyl.

4. Compound according to claim 1 wherein such compound is N (3phenyl-1,2,4-thiadiazol-5-yl)-N'-methyl urea of the formula 5. Compoundaccording to claim 1 wherein such compound isN-(3-isopropyl-1,2,4-thiadiazol-5-yl)-N-methyl- N-metl1yl urea of theformula S OH:

6. Compound according to claim 1 wherein such com- 12 pound is N(3-methyl-l,2,4-thiadiazol-5-yl)-N-methyl- N'-methyl urea of the formula7. Compound according to claim 1 wherein such com pound isN-(3-ethyl-1,2,4-thiadiazol-5-yl)-N-methyl urea of the formula 8.Compound according to claim 1 wherein such compound is N(3-isopropy1-1,2,4-thiadiazol-5-yl) N'- methyl urea of the formula 11.Compound according to claim 1 wherein such compound is N (3isopropyl-l,2,4-thiadiazol-5-yl)-N- ethyl-N-methyl urea of the formulaCzHS N N 00 NH on r r 1 12. Compound according to claim 1 wherein suchcompound is N (3 n-propyl-1,2,4-thiadiazol-5-yl)-N- ethyl-N-methyl ureaof the formula 13. Compound according to claim 1 wherein such compoundis N-(3-isopropyl-1,2,4-thiadiazol-5-yl)-N',N'- dimethyl urea of theformula lCaH1 U N \S/'NHC ON(CH3)1 References Cited Shoeb et al., Chem.Abstracts, 59:7532-3 (1963).

ALEX MAZEL, Primary Examiner R. J. GALLAGHER, Assistant Examiner U.S.Cl. X.R. 7l90 I UNI'IM.) i'ii/fi tcs l w-rbrbii Omar; I CERTIFICATE 01CORRECTIQN tatent No. 3,686,198 Dated August 22, 1972 Inventor(s) CarlMetzger et al' It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

C01, 2 line 22 For I "He" read 1 Col. 3 line' 21 For al 1" read I C01..3 line 66 F ..j I .4 "specially" read especially C01. 4 line 2 read Cieover FORM P040517 (10-69] I :tm'rmtmglc 'rioN Patent No. 3,686,198 tInventor-(s) a Metzger 'et a l It is certified that error appears in-the above-identified patent and that said Letters Patent are herebyeo'rtected as shown below:

Col. 8, Under Sinapis,

the ninth entry,

change "4" to read 5 C01. 10, Under Echinochloa,

Signed. and sealed this 9th day of January 1973 (SEAL) Attest:

EDWARD M;FL ET( IHE R,JR. v I ROBERT GOTTSCHALK Attestlng OfflcerCommissioner of Patents FOR" p 1o5 69) I UQCOMM-DC 8O376-P60

